When my daughter is 40" tall (she is 39" and almost 39 1/2 with shoes on) and the new LO on the way is no longer preventing me from riding rides (January) I totally see us spending more time at Uni than Disney next year. Mainly because the new LO won't be interested in anything until about a year old and my daughter (who will be 4 in December) would much rather ride a coaster or other thrill rides than anything else. Sure she has her moments of wanting Peter Pan, Pooh, and visiting Mickey, but overall she is a thrill seeker. However, I do have friends with kids older than mine who their kids would rather go to Disney. In fact two of my friends with young kids (10 and under) that visit about once a year much prefer Disney because their kids are scared of coasters and other such rides. So it really depends on the kid. My daughter will go on rides that my friends 6 & 9 year olds won't go on.
On a side note, I was pregnant when Hogsmeade opened and couldn't ride anything and now I am pregnant when Diagon opens and again can't ride the main attraction lol I will again be waiting until next year to ride anything. Last time I rode sometime near the end of Jan. This year it probably won't be until February. I will go to see everything else before then though.